* Oxygen is a gas. It's one of the elements that exists naturally in a gaseous state at room temperature.

* Air is a mixture of gases. Air is primarily composed of nitrogen (about 78%), oxygen (about 21%), and a small amount of other gases like argon, carbon dioxide, and others.

So, to answer your question directly:

* Oxygen itself is not a mixture. It's a pure element.

* Oxygen is a component of air, which is a mixture.

Let me know if you have any other questions about elements, mixtures, or the composition of air!